Machine for hollowing shoe lasts



Nov. 1, 1927. 1,647,969

c. L. LNG

HAGHINE FOR HoLowmG SHOE LAsTs Filed April 17. 1924 2 Sheets-Sheet 1 4'V ,A *n Z3 E .11mm am; MEMS/Mw Nov. l, 1927.

C. L. LONG MACHINE FOR HoLLowING SHOE: LAsTs 2 Sheets-Sheet 2 FiledApril 17. 1924 @www Patented Nov. 1, 1927.

UNITED STATES PATENT OFFICE.

cLAUD I.. Lona, or DAYTON, omo, AssIeNon y'ro THD CRAWFORD, Maenneon.AND

CANDY conrANY, or DAYTON, onto, A oonPonATioN or oHIo.

MACHINE FOR HOLLOWING SHOE LASTS.

Application led April 17, 1924. Serial No. 707,300.

This invention relates to shoelast `manufacture, and more particularlyto a machine for recessing or hol display purposes. n

While lasts for shoe manufacturing purposes are ordinarily of solidconstruction., there 'is the demand` for a shoe form for shoe displaypurposes, and as Jfillers for keeping shoes in .proper shape andcontour, for which lo purposes, the ordinaryv shoe lastis unneces?sarily heavy. To meet this demand hollow shoe forms are provided byturning the ordi.` nary shoe last and then recessing the bottom of `thelast quite deeply the recess following in general the contour of thelast, leaving a hollow thin Awalled form'. The usual method of producingsuch hollow Jforms has been by hand operation, or by means of an augerbit, against Vwhich the last to be hollowed is held by hand, the lastbeing tilted and moved to and fro to present it in dier ent relationwith the bit. Such operation is not only dangerous, but the productisuny uniform, and the operation is uneconomical from a manufacturingstandpoint. The present invention contemplates the movement oi' auniversally adjustable cutter head, in relation with a stationarily heldlast, and controlling and limiting its movement by a master Vmodel ofhollow form, within which operates a tracer. In the presentconstruction, the revoluble dependent cutter is belt driven from anelectric motor and carried upon Van adjustable supporting arm having agimbal mounting upon a reciprocatory table. vThe cutter and itssupporting arm are capable of both vertical and lateral oscillation,with reference to the stationarily held work, about the pivots 'of thegimbal mounting, while it is movable 4to and fr0, in a fore and aftdirection, by the sliding adjustment of `the `sliding table.

The object of the invention is to simplify the structure as well as themeans and mode of operation of such hollow Vlast forming devices,whereby lthey will not only be cheapened in construction, but will bemore eiiicient in use, positive in operation, uniform in action andunlikely to get out oit' repair.

A further obj ect of the invention is to provide means kfor hollowingshoe lasts and the like, in which the operation may be con` trolled to`produce duplication of a previously formed recess or cavity, which mayinclude under-cut portions. i

owing shoe lasts for shoe koperated upon, and also for the model 0r A.further object lof the invention is to provide `improved drivingconnections and an adjustable mounting for Vsuch cutter.

A further object ofthe invention is to provide an improved form ofcutter head for operating within a recess or cavity.

With the above primary and other incidental objects in view as will morei'ully appear in the specification, the invention consists of thefeatures of construction, the parts and combinations thereof, and themode of operation or their equivalents as hereinafter described and setforth in the claims.

Refer-ring to the accompanying drawings, wher-ein is shown thepreferred, but obvi ously not necessarily the only form of embodiment ofthe invention, Fig. 1 is a top plan view of the assembled machine. Fig.2 is a side elevation showing the cutter and its supporting arm elevatedand retracted position to 1enable the insertion and removal of the last.Fig. 3 is a rear end elevation illustrating the gimbal Amounting of thecut ter arm andthe sliding table. Fig. l is a front elevation of theassembled machine.` Fig. 5 is a vperspective view of a lhollow shoe formproduced by the present machine. Fig. 6 is afdetail view of the cutterhead. Fig. 7 is a transverse sectional view on line 7,-7 of Fig. 6 andFig. '8 is a transverse sectional View on 'line 8 8 of Fig. 6.

Like parts are indicated by similar characters of reference throughoutthe several views.

In the rvaccompanying drawings, l indicates .the lbase at the forwardend of which is located a support 2 for the last 3 to be guide 4. Anysuitable means may be employed for securing the last to be operated uponand model or pattern form upon the support. In the present instance,clamp jaws have been shown for thispurpose. The work support 2 ispreferably 4though not 100 necessarily mounted kfor oscillatoryadjustment 4upon 4trunnions 5, pivoted in standards 6 and held inadj-usted position by an adjustabile link 7. Slidingly mounted upon thebase l for freciprocatory movement in a 105 fore and att direction, thatis to say, to and from the work support 2,is a `sliding table orcarriage '8. This reci-procatory carriage 8 is preferably ymounted uponrollers or upon ball bearings'9, to facilitate "to and fro move'- 110 inturn is pivoted upon a horizontal axis the driving motor 11. Extendingforwardly from the driving motor 11 and `toward the work support 2 is asupporting arm 12, which for purposes of adjustment and to affordconvenient means for tightening the drive belt is preferably, though notneces'- sarily formed in two interconnected and relatively adjustablesections.v These sections of the arm 12 are held in their adjustedrelation by thek clamp nut 13.,v At its forward end, the arm 12 isprovided with a bearing head 14, in which is revolubly mounted a spindlecarrying at its upper end a small driven pulley interconnected by thebelt 16 with the drive pulley 17, upon the Vupper end of the armatureshaft of the motor 11. The spindle 15 carries at its lower end a bulbouscutter head 18, by which the excess material is removed from the last 3,and the interior of the last hollowed to correspond with the pattern yormodel 4. Projecting laterally from the arm 12, but lixedly connectedtherewith for movement in unison. is a supporting arm 1), having at itsextremity a head 20, from which projects in dependent relation a tracerstem 21, having a bulbous tracer head 22, corresponding in its shape andproportions with those of the cutter head. This tracer head 22 by itsengagement within the recess 4 of they model or pattern last 4, limitsthe range of rcutting action of the cutter head 18 within the last 3being voperated upon. tracer arm, carries a knob or handle 23, while thearm 12 has projecting laterally therefrom a second handle 24. Theoperator standing in frontof the work support 2, and graspingl thehandles 23 and 24 controls the operation of the machine by swinging itfrom side to'side, raising Vand lowering the tracerand cutter head, andpushing and pulling it to andy fro withinl the limits defined by therecess 4 of the model or pattern. The gimbal mounting afforded by theyoke 10 enables substantially universal adjustment of the arm 12, andmaintaining in'all positions constant driving relation with t-he motor11. At the same timel the recipro-` catory movementvof the carriage ortable 8, enables the operation of the device over a comparatively largearea. A standard or rest 25 supports'the arm 12 in elevated relationwhen not in use, and in a retracted position, which permits theinsertion yand removalof lasts and an interchange of patterns or modelswithout interference.

While various. forms ofV cutter heads 18 or other tools maybe employed,,thefpre-v ferred form of .such cutteris of ovoid form,

consisting of two substantially spoon shaped The head 2()v 0f theVcutter blades 26, detachably secured to a head 27 upon the lower end ofthe spindle 15. The convex outer faces of the spoon shaped 'blades 2Gare slightly eccentric lin'relation with each other, to provideclearance. In practice, a bulbous cutter head has been employed in whichthe cutting blades 26 are integral with each other, and also with theattaching motion of the head. However, for convenience of repairs andfor sharpening theblades, it is desirable that they be made independentand be dctachably secured to the support.

n operation the entire device is drawn forward until the cutter head 18is positioned abovethe last 3. It is then pushed downward. cutting intothe last until, the tracer head 22 engages with the bottom of the recesskor cavity 4 in the model last. The cutter head 18 is then moved to andfro transversely by oscillating the arm 12 about the pivotal mounting ofthe yoke 10 and is moved fore and aft by the sliding movement of thetable or carriage 8, until limited by the engagement of the tracer head22 with the lateral walls of the recess or cavity 4', in the model orpattern last. The bulbous form of the cutter head allows the recess orcavity to vbe undercut or inwardly widened through the heel portion andarch portion of the` last. By following the interior walls of the recess4 with the spacer head 22, thefcutter head 18 is caused tor follow thesame course of travel within the body of the last 8, and by its removalof excess material duplicates the recess of the model or pattern last.By this means the interior of the last can be contoured with extremeaccuracy to lafford comparatively thin walls of uniform, thicknessthroughout, or with such variations of contour and thickness as may bepresent in the model.

It has been found in practice'that a skilled workman, hy exercise o'ljudgment and care can recess a last to the required extent without theuse of the model and'tracer. In such case the cutter is moved to and froas before described, but without the limitations imposed by the model.Reliance is placed entirelyv upon the skill and judgment of the workmantogether with'a certain sense of feel which is the development of askilled artisan. Models are initially produced by such4 method and by askilled operator, to be subsequently employed by less skilled workmenforduplication by means of the tracer methodof movement limitation.

While themachine is described as producing but vone duplication oftherecessed model ata time, it is obvious that the head may be providedwith multiple spindles and cuttersoperating simultaneously upon a numberof different lasts and controlled from the same master model. Sucharrangement is indicated by dotted lines in Fig. l.

lll)

`From the above description it will b'e a vertical axis, an adjustablecarrier for the apparent that there is thus provided a device of thecharacter described possessing the particular features of advantagebefore enumerated as desirable, but which obviously is susceptible ofmodification in its form, proportions, detail construction andarrangement of parts without departing from the principle involved orsacrificing any of its advantages.

lllhile in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificdetails shown, but that the means and construction herein disclosedcomprises the preferred form of several modes of putting the inventioninto effect and the invention is, therefore, claimed in any of its formsor modifications within the legitimate and valid scope of thek apypended claims.

I'Iaving thus described my invention, I claim:

l. In a machine of the character described, stationary work and modelsupports, an electric motor movable toward and from the work and mod-elsupports, a reciprocatory mounting for the motor upon which the motormounted for oscillatory movement about both vertical and horizontalaxes, an arm fixedly connected with the motor and movable in unison withthe reciprocatory and oscillatory movement thereof, a tracer gage forengagement with the model, a rev* oluble cutting tool for engagementwith the wei-l; carried by the arm, and a drive belt therefor,operatively connecting the cutting tool with the electric motor saidtracer being;` enabled to follow the model by the to and froreciprocatory movement of the motor mounting in conjunction with thevertical and lateral swinging movements of the arm to enable the 'cutterto follow the same lines of movement upon the work.

2. In a machine of the character described, a work holder, a cuttingtool revolving on tool, movable longitudinally, transversely andvertically relative to the work holder, a tracer in `fixed relation withthe tool and movable to and fro in unison therewith, an electric motorlocated in fixed relation with the cutter and movable in unisontherewith, and an operative driving connection between the motor and thecutter by which the cutter is uniformly operated in all positions ofadjustment. y 3. In a machine of the character described, a stationarywork holder, a sliding carriage mounted for reciprocatory movementtoward and from said Work holder, a motor mounting upon the carriagecapable of oscillatory movement to and fro about an axis perpendicularto the plane of movement of the carriage, a motor pivoted in saidmounting for oscillatory movement about an axis substantiallyperpendicular to the axis of oscillation of the motor mounting, an armlixedly attached to the motor and radially disposed in relation with theaxes of oscillation of the motor, a revoluble cutter rotating on asubstantially vertical axis and a tracer located in fixed relation withthe cutter carried by the arm and a drive belt affording operativeconnection between the motor and cutter for operating the cutter in allpositions of adjustment of the arm and motor.

4. In a machine of the character described, stationary work and modelholders, a revoluble cutterprotating about a substantially verticalaxis, a driving motor operatively connected with the cutter, a tracergage mounted in fixed relation with the cutter, and a mounting uponwhich the cutter and motor are mount-ed in relatively fixed relationwith each other, but capable of to and fro'horizontal, and vertical andtransverse swinging movements, the relative relation of t-he drivingmotor and cutter being maintained constant in all positions ofadjustment. In testimony whereof, I have hereunto set my hand this 8 dayof April, A. D. 1924. CLAUD L. LONG.

